1. Field of the Invention
This invention relates to a biochemical analysis unit for use in an operation for detecting a receptor or a ligand by the utilization of a labeling substance.
2. Description of the Related Art
Heretofore, in the fields of clinical examinations, and the like, analyses of various samples have been made. Also, in order for quick and accurate analyses of the samples to be made, various analysis implements for use in analysis kits and analysis instruments have been proposed. For example, in Japanese Patent No. 3298836, a sample analysis implement comprising an analyzing section and a porous sample introducing section, which has a mean pore diameter larger than the mean pore diameter of the analyzing section, is proposed. The proposed sample analysis implement, wherein the mean pore diameter of the porous sample introducing section is set to be large, and wherein the mean pore diameter of the analyzing section is set to be small, enables the separation of constituents of a sample, such that the sample may be processed quickly.
Also, in the fields of molecular biology, such as genetic expression analysis, macro arrays comprising a membrane and a plurality of spots (dots), which contain biopolymers, such as DNA's, and are arrayed on the membrane, have heretofore been known. With the macro arrays, multiple kinds of samples are capable of being analyzed at one time on a single membrane. Therefore, the macro arrays have heretofore been used widely in the fields of molecular biology and the medical fields. For example, various kinds of DNA fragments (probes) may be arrayed in the form of dots on the macro array, and a target, which has been prepared from mRNA, or the like, may be added onto the macro array. In this manner, hybridization, or the like, may be caused to occur. In such cases, behavior of a plurality of genes can be analyzed at one time.
The conventional macro arrays are constituted of a polymeric organic membrane formed from nitrocellulose, or the like. Therefore, the conventional macro arrays are markedly soft and are apt to suffer from bending and creasing, which adversely affects the analytic operations, and the like. Accordingly, a macro array comprising a film-shaped hard porous body and a plurality of spots, which contain test substances and are arrayed on the film-shaped hard porous body, has been proposed in, for example, U.S. Pat. No. 6,492,119.
Also, various micro array analysis systems and various macro array analysis systems have heretofore been used. With the micro array analysis systems and the macro array analysis systems, liquids containing ligands or receptors (i.e., the substances, which are capable of specifically binding to organism-originating substances and whose base sequences, base lengths, compositions, characteristics, and the like, are known) are spotted onto different positions on a surface of a biochemical analysis unit, such as a membrane filter, and a plurality of adsorptive regions are thereby formed on the surface of the biochemical analysis unit. Examples of the ligands or the receptors include hormones, tumor markers, enzymes, antibodies, antigens, abzymes, other proteins, nucleic acids, cDNA's, DNA's, and RNA's. Thereafter, a labeled receptor or a labeled ligand, which has been labeled with a radioactive labeling substance, a fluorescent labeling substance, a labeling substance capable of causing a chemical luminescence substrate to produce chemical luminescence when being brought into contact with the chemical luminescence substrate, or the like, is subjected to hybridization, or the like, with the ligands or the receptors, which are contained in the adsorptive regions of the biochemical analysis unit. The labeled receptor or the labeled ligand is thus specifically bound to at least one of the ligands or the receptors, which are contained in the adsorptive regions of the biochemical analysis unit. The labeled receptor or the labeled ligand is the substance, which has been sampled from an organism through extraction, isolation, or the like, or has been subjected to chemical treatment after being sampled, and which has been labeled with the radioactive labeling substance, the fluorescent labeling substance, the labeling substance capable of causing a chemical luminescence substrate to produce the chemical luminescence when being brought into contact with the chemical luminescence substrate, or the like. Examples of the labeled receptors or the labeled ligands include hormones, tumor markers, enzymes, antibodies, antigens, abzymes, other proteins, nucleic acids, DNA's, and mRNA's.
In cases where the labeled receptor or the labeled ligand has been labeled with the radioactive labeling substance, a stimulable phosphor layer of a stimulable phosphor sheet is then exposed to radiation radiated out from the radioactive labeling substance, which is contained selectively in the adsorptive regions of the biochemical analysis unit. Thereafter, the stimulable phosphor layer is exposed to stimulating rays, which cause the stimulable phosphor layer to emit light in proportion to the amount of energy stored on the stimulable phosphor layer during the exposure of the stimulable phosphor layer to the radiation. The light emitted by the stimulable phosphor layer is detected photoelectrically, and data for a biochemical analysis is thereby obtained.
In cases where the labeled receptor or the labeled ligand has been labeled with the fluorescent labeling substance, excitation light is irradiated to the adsorptive regions of the biochemical analysis unit, and the fluorescent labeling substance, which is contained selectively in the adsorptive regions of the biochemical analysis unit, is excited by the excitation light to produce fluorescence. The thus produced fluorescence is detected photoelectrically, and data for a biochemical analysis is thereby obtained.
In cases where the labeled receptor or the labeled ligand has been labeled with the labeling substance capable of causing a chemical luminescence substrate to produce the chemical luminescence when being brought into contact with the chemical luminescence substrate, the labeling substance, which is contained selectively in the adsorptive regions of the biochemical analysis unit, is brought into contact with the chemical luminescence substrate. Also, the chemical luminescence produced by the labeling substance is detected photoelectrically, and data for a biochemical analysis is thereby obtained.
The micro array analysis systems and the macro array analysis systems are described in, for example, U.S. Patent Laid-Open No. 20020061534.
With the micro array analysis systems and the macro array analysis systems described above, a large number of the adsorptive regions, to which the ligands or the receptors are bound, are capable of being formed at a high density at different positions on the surface of the biochemical analysis unit, and the labeled receptor or the labeled ligand, which has been labeled with the labeling substance, is capable of being subjected to the hybridization, or the like, with the ligands or the receptors, which have been bound to the adsorptive regions formed at a high density at different positions on the surface of the biochemical analysis unit. Therefore, the micro array analysis systems and the macro array analysis systems described above have the advantages in that a receptor or a ligand is capable of being analyzed quickly.
[Patent Literature 1]
Japanese Patent No. 3298836
[Patent Literature 2]
U.S. Pat. No. 6,492,119
[Patent Literature 3]
U.S. Patent Laid-Open No. 20020061534
However, the ligand or the receptor, which is bound to each of the adsorptive regions of the biochemical analysis unit described above, is bound and fixed to the entire area of each of the adsorptive regions. Therefore, the problems occur in that a signal coming from the receptor or the ligand having been bound to the ligand or the receptor having been fixed to an area of each of the adsorptive regions, which area is remote from a detection surface, is attenuated. As for the micro array analysis systems and the macro array analysis systems described above, it is desired that the receptor or the ligand be capable of being analyzed more accurately. However, the attenuation of the signal described above obstructs the formation of accurate data for a biochemical analysis.